Centrifugal separator



June 4, 1935. G. H. ANDERSSON CENTRIFUGAL SEPARATOR Filed Jan. 16, 19332 Sheets-Sheet l //IIIIII June 4, 1935- e. H. ANDERSSON 2,003,521

CENTRIFUGAL SEPARATOR Filed Jan. 16, 1933 2 Sheets-Sheet 2 Patented June4, 1935 UNITED STATES 2,003,821 cam-airman summon GnstavHn-ry Stockholm,Smil- Anderson, signer to The De Laval Separator Company, New York, N.Y., a corporation of New Jersey AppIicaflonJanIary InGermany lclnlms.

This invention relates to centrifugal separators and is moreparticularly applicable to that type of separator wherein the admissionliquid' or mixture of liquids contains solids, some of which are lighterand some of which are heavier than the liquid, the main function of thesepa-' rator being to purify the liquid.

At the conclusion of the separating operation, a certainamount of liquidremains in the bowl, which, in many cases, as, for example, in thepurification of volatile scom'ing liquids such as trichlorethylene andcarbon tetrachloride, gives rise to trouble in the dismantling andcleaning of the bowl, owing to the evolution of dangerous gases.

In an application filed by Stig Beskow September 14, 1932, Serial No.633,034, drain channels are provided in the bottom of the bowl or in aseparate member in the bottom of the bowl, the drain channelscommunicating with the bowl chambers and discharging adjacent the axisof revolution of the bowl.

The present invention involves certain improvements in the Beskowinvention. Said improvements comprise means for blowing steam or a hotgas through the bowl to remove any liquid that may adhere to the variousparts of v the bowl and to the separated solids remaining operation, toclose the heavier liquid discharge opening of the bowl, so as to insurethe passage of all the drying gas through the described drain channels.This closure, as well as the closure of the annular opening at the feedinlet, is veiifected, in my preferred construction, by a single packingdevice readily movable into operative position before drying and out ofopera tive position preparatory to starting the bowl.

The invention also comprises an improvement in the drain channels, whichis hereinafter particularly described.

The constructions set forth in the said Beskow application areillustrative of centrifuges to which my invention is applicable. Inorder to fully disclose my invention, I have herein illustrated acentrifugal bowl comprising features disclosed in the Beskow applicationin connec- 18. 193:, Serial No. 51,915 September 14, 19::

tion with other features illustrative of my in-.

vention.

Fig. 1 is an elevation, partly in section, of a centrifugal bowl andappurtenant parts.

Fig. 2 is an elevation, partly in section. of the bowl.

Fig. 3.is a horizontal section'through the line 33 of Fig. 2. Thecentrifugal bowl I is enclosed by the upper part 2 of the frame and by acover 3 containing the collecting vessel or vessels. The

top of the cover has a hollow boss 32, from which depends a tube or pipe5 extending into the distributor, 6, which may have a tubular or a.frustro-conical shape. At the top the hollow boss 32 carries an elbow33, to which is secured a supply pipe I.

The mixture to be separated is admitted to part 6 of the bowl throughpipe I and tube 5. The bowl may be divided .by means of cylindricalpartitions l3 and I4 into annular chambers l5, l6 and I1, through whichthe liquid successi'vely streams as indicated by the arrows. Theseparated solids deposit on the outside or inside walls of therespective chambers, dependent on whether such solids are heavier orlighter than the liquid. The purified liquid, or the heavierof twoliquids if the mixture contains more than one liquid, is discharged fromthe bowl through the channel It and streams out between the distributori and the neck of the bowl into the collecting vessel in the cover anddischarges therefrom through conduit 1.

When the rotation of the bowl ceases, the chamber l5 empties out throughthe channels 8 and the chambers l6 and I1 empty out through the channels9; chambers l6 and I1 being connected'at their lower ends by overflowchannels 20. As the outer ends of the channels I and 9 are situatedinside the free level of liquid in the bowl, 9. flow of liquid cannotoccur through these channels during the separation, and for this reasonlarge quantities of solids cannot deposit in them. The drainage liquidfrom channels 8 and 9 flows into the chamber HI and thence, through aconduit ll, into a collecting tank 12, which is suitably connected, bymeans not shown, with a plant for the separation of securing liquid.

After the bowl has been stopped and the liquiddrained out, steam orsuitable gas is blown into the bowl through apipe 23 connected with thesupply pipe 4, the gas or steam escaping through the liquid dischargechannel l8 and through the drain channels 8 and 9.-

Instead of introducing the steam or gas through the pipes 23 and I,suction may be applied in these pipes to draw gas or steam through thebowl in the reverse direction.

The effect of the gas stream would be enhanced if all the gas enteringor leaving the bowl were compelled to flow through the drain channels 8and 9. In Fig. 1 this is-accomplished by means of an annular flangedclosure or packing 25 having a sliding fit on tube 5 and movabledownward, by means of a rod 26, so as to engage the upper edges of thefeed tube 6 and the bowl neck, thereby closing both the inlet; to thebowl and the heavy liquid outlet. Thus it is possible to drive all thesteam through the bottom outlets and clean out any of them that may bepartly closed. If it is desired to not close the channel 18 to thepassage of drying gas, the downwardly depending annular flange of theclosure 25 is omitted.

Each of the drain channels 8 and 9 is, between its ends, expanded andthen sharply contracted to form a collecting chamber 21, in which anysolids separated in the channels are deposited. Owing to the greatthroughflow area in the chambers, the layer of deposited solids is verythin and is therefore easily broken up by the liquid when the bowlstops. It is advantageous to position the chambers 21 at such a distancefrom the rotation axis of the bowl that a free level is formed in them.The entrance ends of the drain chanenls should be suiliciently narrowtoinsure a minimum of exchange of liquid between the annular chambersl5, l6 and I1 and the channels, so that, also, a minimum deposit ofsolids occurs in the drain channels. To this end the entrance ends ofeither or both sets of channels may be restricted.

If the liquid to be separated consists of a mixture of liquids, theseparated lighter components collect near to the rotation axis of thebowl in the chamber l5, whence it discharges through channels 301 Inorder to prevent these channels from becoming clogged by light solidsdepositing therein, it is advantageous to provide a straining orfiltering device in the chamber l5. Such device may consist of acylindrical reticulated member 3|, such as a perforated metal cylinderor a wire mesh screen.

What I claim and desire to protect by Letters Patent is:

1. The combination with a centrifugal separator bowl having an open topand a centrally positioned supply tube extending into the open top ofthe bowl and spaced therefrom to form an annular opening, said bowlhaving drainage channels in its bottom part, means operative throughsaid supply tube to admit to or exhaust from the bowl a drying gas, of aclosure for said annular opening and means to move the closure relativeto the bowl and feed tube into and out of position to close the opening.

2. The combination with 'a centrifugal separator bowl having an open topand a centrally positioned supply tube extending into the open top ofthe'bowl and spaced therefrom to form an annular opening, said bowlhaving drainage channels in its bottom part, means operative throughsaid supply tube to admit to or exhaust from the bowl a drying gas, of apacking sleeve having a sliding fit on said supply tube and movablevertically into position to abut against the circumferential edge ofsaid annular opening to prevent the passage of drying gas through saidopening.

3. The combination with a centrifugal separator bowl having an openneck, a centrally positioned supply tube extending into and spaced fromthe neck of the bowl, means operative through said supply tube to admitto or exhaust from the bowl a drying gas, a distributor extending intothe bowl neck and spaced from both the supply tube and the bowl neck andproviding annular openings between the supply tube and distributor andbetween the distributor and the bowl neck, said bowl having drainagechannels in its bottom part, of means movable into and out of positionto close both said openings.

4. The combination with a centrifugal separator bowl having an openneck, a. centrally positioned supply tube extending into the neck of thebowl, a distributor extending into the bowl neck and spaced from boththe supply tube and the bowl neck, said bowl having drainage channels inits bottom part, of a packing sleeve having a sliding fit on said supplytube and movable vertically into position to abut against thecircumferential upper edges of the bowl neck and distributor to closethe openings inside the bowl neck and outside the supply tube during thepassage of a drying gas through the bowl and said drainage channels.

5. A centrifugal separator bowl having concentric annular separatingchambers and drainage channels in the bowl bottom communicating withsaid separating chambers and extending inward toward and dischargingadjacent the axis of rotation, said channels being widened between theirends to form between their ends chambers for the deposit of separatedsolids.

6. A centrifugal separator bowl having concentric annular separatingchambers and drainage channels in the bowl bottom communicating withsaid separating chambers and discharging adjacent the axis of rotation,said channels being widened between their ends to form chambers for thedeposit of separated solids, and being narrowed at their .entrance endsto minimize the exchange of liquid between the annular separatingchambers and the channels during the normal operation of the bowl.

7. The combination with a centrifugal separator bowl having an open topand a centrally positioned supply tube extending into the open top ofthe bowl and spaced therefrom to form an annular opening, said bowlhaving drainage channels in its bottom part, said supply tube alsoaffording means to admit to or exhaust from the bowl a drying gas, of aclosure surrounding said feed tube and extending over said annularopening, means extending through the cover and adapted to support saidclosure above and spaced from said opening, said means being adjustableto move'said closure down into position to seal said opening preparatoryto blowing a cleaning fluid through the bowl.

8. The combination with a centrifugal separator bowl having an openneck, a centrally positioned supply tube extending into and spaced fromthe neck of the bowl, a distributor extending into the bowl neck andspaced from both the supply tube and the bowl neck and providing annularopenings between the supply tube and distributor and between thedistributor and the bowl neck. said bowl having drainage channels in itsbottom part, of means movable into and out of position to close bothsaid openings, said means comprising a disc enclosing the feed tube andmovable thereon and an annular flange on the disc in alignment with thebowl neck.

GUSTAV HARRY ANDERSSON.

